With the development of wireless communication technology, demands of a user for high quality, a high speed, a new service is higher and higher. A wireless communication operator and a device manufacturer should continuously improve a system to meet the demands of the user. In this case, a large amount of spectrum resources are required to support the new service arising continuously, and to meet requirements of high-speed communications, and the spectrum resources may be quantized with a parameter such as time, frequency, band width, allowable maximum emitting power.
Currently, limited spectrum resources have been allocated to fixed operators and services, new available spectrum is very rare or expensive. Yet, a large number of actual measurement results indicate that generally the utilization rate of the allocated licensed spectrum is not high. In this case, a concept of dynamic spectrum usage is proposed, that is, spectrum resources which have been allocated to certain services but are not utilized sufficiently are utilized dynamically.